GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

  1. Partially drain the cooling system. Refer to Cooling System Draining and Filling .
  2. Remove the intake manifold cover. Refer to Intake Manifold Cover Replacement .
  3. Remove the oil level indicator and tube. Refer to Oil Level Indicator and Tube Replacement .

  4. Object Number: 1608802  Size: SH
  5. Remove the left side spark plug wires from the vehicle.

  6. Object Number: 1608801  Size: SH
  7. Remove the positive crankcase ventilation (PCV) foul air tube. Refer to Plastic Collar Quick Connect Fitting Service .

  8. Object Number: 1608325  Size: SH
  9. Reposition the heater inlet and outlet hose/pipe clamps at the engine inlet and outer pipes.
  10. Remove the heater inlet and outlet hose/pipe clip nuts at the throttle body.
  11. Remove the heater inlet and outer hoses/pipes from the engine inlet and outlet pipes.
  12. Remove the clips from the throttle body studs. Reposition the hose/pipe assembly.

  13. Object Number: 1608994  Size: SH
  14. Remove the front heater outlet hose from the outlet heater pipe.
  15. Remove the heater inlet and outlet pipe bolt and stud.
  16. Remove the heater inlet and outlet pipe from the vehicle.

  17. Object Number: 1609161  Size: SH
  18. Loosen the left side valve rocker arm cover bolts.
  19. Important: When removing the left side valve rocker arm cover, ensure the left side valve rocker arm cover gasket stays in place attached to the left side cylinder head.

  20. Remove the left side valve rocker arm cover. If necessary, bump the end of the left side valve rocker arm cover with the palm of your hand or a soft rubber mallet if the cover adheres to the cylinder head.
  21. Cut the RTV in the channel where the lower intake manifold, left side cylinder head and left side valve rocker arm cover meet with a suitable tool.
  22. Remove the left side valve rocker arm cover gasket.
  23. Clean the sealing surface on the cylinder head with degreaser.

Installation Procedure

Important: All gasket mating surfaces need to be free of oil and foreign material. Use cleaner to clean the surfaces. Refer to Adhesives, Fluids, Lubricants, and Sealers .


    Object Number: 190588  Size: SH
  1. Install a NEW left side valve rocker arm cover gasket into the groove in the left side valve rocker arm cover. Ensure that the gasket is properly seated.
  2. Apply sealant at the left side cylinder head to the surfaces where the left side cylinder head and lower intake manifold meet (1). Refer to Adhesives, Fluids, Lubricants, and Sealers .

  3. Object Number: 1609161  Size: SH
  4. Install the left side valve rocker arm cover.
  5. Notice: Refer to Fastener Notice in the Preface section.

    Important: Use an alternating criss-cross pattern when tightening the left side valve rocker arm cover bolts. Failure to do so may result in oil leakage due to improper seating of the gasket.

  6. Tighten the left side valve rocker arm cover bolts.
  7. Tighten
    Tighten the bolts to 10 N·m (89 lb in).


    Object Number: 1608994  Size: SH
  8. Install the heater inlet and outlet pipe to the vehicle.
  9. Install the heater inlet and outlet pipe bolt and stud.
  10. Tighten

        • Tighten the bolt to 25 N·m (18 lb ft).
        • Tighten the stud to 10 N·m (89 lb in).
  11. Install the front heater outlet hose to the outlet heater pipe.

  12. Object Number: 1608325  Size: SH
  13. Position the hose/pipe assembly. Install the clips to the throttle body studs.
  14. Install the heater inlet and outer hoses/pipes to the engine inlet and outlet pipes.
  15. Install the heater inlet and outlet hose/pipe clip nuts at the throttle body.
  16. Tighten
    Tighten the nuts to 10 N·m (89 lb in).

  17. Position the heater inlet and outlet hose/pipe clamps at the engine inlet and outer pipes.

  18. Object Number: 1608801  Size: SH
  19. Install the PCV foul air tube. Refer to Plastic Collar Quick Connect Fitting Service .

  20. Object Number: 1608802  Size: SH
  21. Install the left side spark plug wires.
  22. Install the oil level indicator and tube. Refer to Oil Level Indicator and Tube Replacement .
  23. Install the intake manifold cover. Refer to Intake Manifold Cover Replacement .
  24. Fill the cooling system. Refer to Cooling System Draining and Filling .

Removal Procedure

  1. Partially drain the cooling system. Refer to Cooling System Draining and Filling.
  2. Remove the intake manifold cover. Refer to Intake Manifold Cover Replacement.
  3. Remove the oil level indicator and tube. Refer to Oil Level Indicator and Tube Replacement.

  4. Object Number: 1608802  Size: SH
  5. Remove the left side spark plug wires from the vehicle.

  6. Object Number: 1608801  Size: SH
  7. Remove the positive crankcase ventilation (PCV) foul air tube. Refer to Plastic Collar Quick Connect Fitting Service.

  8. Object Number: 1608325  Size: SH
  9. Reposition the heater inlet and outlet hose/pipe clamps at the engine inlet and outer pipes.
  10. Remove the heater inlet and outlet hose/pipe clip nuts at the throttle body.
  11. Remove the heater inlet and outer hoses/pipes from the engine inlet and outlet pipes.
  12. Remove the clips from the throttle body studs. Reposition the hose/pipe assembly.

  13. Object Number: 1608994  Size: SH
  14. Remove the front heater outlet hose from the outlet heater pipe.
  15. Remove the heater inlet and outlet pipe bolt and stud.
  16. Remove the heater inlet and outlet pipe from the vehicle.

  17. Object Number: 1609161  Size: SH
  18. Loosen the left side valve rocker arm cover bolts.
  19. Note: When removing the left side valve rocker arm cover, ensure the left side valve rocker arm cover gasket stays in place attached to the left side cylinder head.

  20. Remove the left side valve rocker arm cover. If necessary, bump the end of the left side valve rocker arm cover with the palm of your hand or a soft rubber mallet if the cover adheres to the cylinder head.
  21. Cut the RTV in the channel where the lower intake manifold, left side cylinder head and left side valve rocker arm cover meet with a suitable tool.
  22. Remove the left side valve rocker arm cover gasket.
  23. Clean the sealing surface on the cylinder head with degreaser.

Installation Procedure


    Object Number: 190588  Size: SH

    Note: All gasket mating surfaces need to be free of oil and foreign material. Use cleaner to clean the surfaces. Refer to Adhesives, Fluids, Lubricants, and Sealers.

  1. Install a NEW left side valve rocker arm cover gasket into the groove in the left side valve rocker arm cover. Ensure that the gasket is properly seated.
  2. Apply sealant at the left side cylinder head to the surfaces where the left side cylinder head and lower intake manifold meet (1). Refer to Adhesives, Fluids, Lubricants, and Sealers.

  3. Object Number: 1609161  Size: SH
  4. Install the left side valve rocker arm cover.
  5. Caution: Refer to Fastener Caution in the Preface section.

    Note: Use an alternating criss-cross pattern when tightening the left side valve rocker arm cover bolts. Failure to do so may result in oil leakage due to improper seating of the gasket.

  6. Tighten the left side valve rocker arm cover bolts to 10 N·m (89 lb in).

  7. Object Number: 1608994  Size: SH
  8. Install the heater inlet and outlet pipe to the vehicle.
  9. Install the heater inlet and outlet pipe bolt and stud.
  10. • Tighten the bolt to 25 N·m (18 lb ft).
    • Tighten the stud to 10 N·m (89 lb in).
  11. Install the front heater outlet hose to the outlet heater pipe.

  12. Object Number: 1608325  Size: SH
  13. Position the hose/pipe assembly. Install the clips to the throttle body studs.
  14. Install the heater inlet and outer hoses/pipes to the engine inlet and outlet pipes.
  15. Install the heater inlet and outlet hose/pipe clip nuts at the throttle body and tighten to 10 N·m (89 lb in).
  16. Position the heater inlet and outlet hose/pipe clamps at the engine inlet and outer pipes.

  17. Object Number: 1608801  Size: SH
  18. Install the PCV foul air tube. Refer to Plastic Collar Quick Connect Fitting Service.

  19. Object Number: 1608802  Size: SH
  20. Install the left side spark plug wires.
  21. Install the oil level indicator and tube. Refer to Oil Level Indicator and Tube Replacement.
  22. Install the intake manifold cover. Refer to Intake Manifold Cover Replacement.
  23. Fill the cooling system. Refer to Cooling System Draining and Filling.